5-11 thumb.url是什么东东

$ brew install imagemagick
class MyUploader < CarrierWave::Uploader::Base
include CarrierWave::MiniMagick
process resize_to_fit: [800, 800]
version :thumb do
process resize_to_fill: [200,200]
end
end
When this uploader is used, an uploaded image would be scaled to be no larger than 800 by 800 pixels. A version called thumb is then created, which is scaled and cropped to exactly 200 by 200 pixels. The uploader could be used like this:
uploader = AvatarUploader.new
uploader.store!(my_file) # size: 1024x768
uploader.url # => '/url/to/my_file.png' # size: 800x600
uploader.thumb.url # => '/url/to/thumb_my_file.png' # size: 200x200